Conveyer switching system



Oct. 21, 1952 l K. MULLERHEIM .2,614,506

lvCONVEYER SWITCHING SYSTEM Filed March 11, 1946V 5 Sheets-Sheet l To TRACK f\.. sw T U HUNDREDS ja E' D o lll 4 4 1 a7 ga STATION sT .1' Ns sTA.uN|Ts SELECTOR SWITCH SEC. sEw. ssl.. sw.

ATTORNEY .Oct- 21, 1952 K. MULLERHEIM 2,614,506

CCNVEYER SWITCHINC SYSTEM Filed March 11, 1946 5 sheets-sheet 2 A.c. l g Y 1f v j A' +11 To' TRACK sw. 5

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INVENTOR. KURT MULLERHEIM Oct. 21, 1952 K. MULLERHEIM coNvEYER swITcHING SYSTEM `Filed March 1l. 1946 3 Sheets-Sheet 5 r/ L? l l,

TRACK CONTACT PLATE CARRIAGE FIG. 6

INVENTOR. KURT MULLERHEIM BY @my OPER. Imm-mp4 ATTORNEY Patented Oct. 21, 1952 UNITED-ESTATES PATENT OFFICE 'j l d f 2,614,506

`f coNvEYEn sWIToHiNG SYSTEM Y `Kurt Mullerheim, New York, N. Y., assignor to Automatic Electric Laboratories, Inc., Chicago, Ill., a corporation of Delaware Application March 11, 1946,`Serial No. $53,513

This invention relates to conveyor systems, and

particularly to electrically operated conveyor sys-y tems such kas commonly ,usedv in various types of industrial establishments for.v the transportation of goodsand materials from point to point. It is directed particularly to anoverhead monorail system or the like in which one. or more selfpropelled carriers orvehicles operate over a closed track from one or more loadingordispatching stations to a plurality of unloading or handling stations, and back to the dispatching'stations for re-use.- The dispatching and handling stations are preferably located on individual sidings or? branch tracks, so as not to interfere. with thefree;

passage or vehicles bound for other points in the system. v

In such a systerneach carrier or vehicleis provided with a driving motor, electrically .operated from a trolley or bus paralleling the track. If this bus be divided into separateblocksorysections, said vehicles may readily bejstopped in any section by remote control, from a centralv point,

by disconnecting the power fromwthe, bus of said` section. Where branch tracks and electrically, operated track` switches areA employed, remote; control of the track switches from acentral pointv The main object of my-invention, is therefore the provision of a simple self-switching and control means for such va system wherein the various vehicles automatically switch themselves into the various branch tracks or sidings as'req'uired by, automatically operating the 'associated' .track switches upon arrival thereat, vin accordance with' simple adjustmentsmade on said vehicle before its departure.

Another object'of my invention` is the'uu1ization of the same means for causing said vehicles to stop automatically at a particular, handling" station as predetermined, in cases where two orf more such stations may be provided in a 'single' branch track or siding.

-A further object vozfmy invention is 'thel utiliza-l tion of the same or similar'means for causing said vehicles to switch themselves automatically into a particular dispatching station branch track, on arriving thereat, which may 'ormay lnot s claims. (ci. i-ss) be the same branchl track from which it was originally dispatched. Still another object is the provision of a system of large capacity and flexibility with a minimum of trackside control equipment, and a minimum or line conductors between the various points of. the. system.

One feature of the invention, to which the system owes much of its capacity, lflexibility and simplicity, is the provision on each vehicle of a small group of primary control relays capable of being operated in a large number of combinations by a small number of trackside contact plates or buses at each track-switch or station location, as the vehicle arrives at said locations. Contacts on the relays are operated in corresponding combinations to prepare circuits for the operation of the corresponding track switches or other trackside equipment, as required. v

IAnother featureis the arrangement of the relays in groups corresponding to the digits of a vnumber characterizing each branch and station location. Y

Another feature is the manner in which the relay-controlling trackside contact plates are marked with various electrical potentials from asingle source of alternating current, by means of operation of predetermmed track switches or simple crossconnections and the use of dry disc rectiers. v ,Y

Still` another featurevis the provision on the outside of each vehicle Vof a number oi multi- Vpoint, hand-operated switches, which may be quickly and easily adjusted by a dispatcher before the kvehicles departure from his station, to preselect one or more of the .aforementioned circuits through the contacts of the relays, to cause the other trackside equipment, for the guidance of said vehicle, whereby it may be caused Vto direct itself to any desired handling station and 'to return to any desreddispatching station.

Other objects and features of the invention will be apparent from 'the following description and claims, and from lthe accompanying drawings comprising Figures 1 to 6, inclusive, which are also a part of "they specication.

With reference to the drawings, Figure 1 shows v the circuit arrangement for one embodiment oi' the invention, and Figure 2 a typical schematic track layout for such a system, in which the ,handling branch ytracks are arranged in two divisions, with a single station per branch track.

Figure 3 shows a modified circuit arrangement for cases where two or more stations are required in each branch track, and Figure 4 is a typical track layout for such a system. These arrangements are of course merely representative, and are subject to an almost limitless number of variations, as will be apparent on further study. Figure 5 shows a diagonal side view of a section of track for a typical monorail conveyor system with a carriage in place, and Figure 6 is a schematic plan diagram of a switch location, showing a `siding entrance with track switch and contact plates and an approaching carriage. It will be understood that other forms of track and carriage may be used if desired.

In Figure l, the trackway equipment directly involved in the invention, is shown in the upper part of the drawing, encompassed by the bracket 4I. This represents the equipment for a single branch track or station such as station 324, in# dicated on the lower left in Figure 2. The re lated equipment carried by the vehicle, which is identical for each vehicle, is indicated by the bracket 42.

In the trackway equipment 4I, the trackside contact plates are indicated by the numerical designations 9, II, I3 and I5. The operating or switching contact vplate I5 vis shown connected to one side of a trackside relay 5, the other side of which is permanently connected to a common source of alternating, current, by way of the common conductor I. Relay 5 is normally `provided with locking contacts 6, and operating contacts 1 which control the track'switch. Contacts 8 are a 'special pair of break contacts located in the trackway beyond the track switch, and are operated by the vehicle 'as it passes, to release relay 5 land thereby re-set the track switch for the main track, after the vehicle has passed into the branch track.

The combination contact plates comprising the hundreds marking plate 9, the tens marking plate Il, and the units marking plate I3, may be left open, or may be vc'ross-connected to conductor l in various ways by means of a direct strap or jumper such as 4,- or by special straps such as 2 and 3, comprising dry disc rectiers in series, and poled as required. As' shown, the sti-'ap 4 for example, will connect an alternating voltage to plate I3, while strap 3 will connect `a positive direct current voltage to plate II, and strap `2 a negative direct current voltage to plate 9, it rbeing assumed that current will ow freely through the rectifier discs in the direction indicated by the arrow heads, and onlyjto an insignicant degree in the opposite direction. It is thus apparent that any one of the three marking plates at any station may be marked with any one of four voltage conditions, namely: J(1) No voltage; (2) Alternating voltage; (3) Positive direct current voltage; (4) Negative direct current voltage. With three marking plates, this makes va total of 4 4= 4A or 64 possible combinations. Similarly, with four marking 'plates per station, 4X4 4 4 or 256 'combinations would be possible, and so on. Even this however, does not define the ultimate capacity of 'the system, since, by dividing the branch tracks into divisions, the basic capacity of the system is increased in direct multiples, less the number of divisions, as will be shown. Actually, it is vproposed to utilize only 63 combinations inall, omitting the 1--1-1, or all-relays-normal" combination. Also, some combinations will need to be lreserved for dispatching station use.

`of the pair.

In the vehicle-borne equipment 42, the combination relays 32 and 29 are connected in series with the hundreds collector shoe I0, the combination relays 26 and 23 are in series with the tens collector shoe I2, and the combination relays 20 and I1 are connected to the units collector shoe I4. The other side of each pair of these relays is shown connected to a common collector shoe 39, which normally rides on the ground bus 40, which is also the other side of the alternating current source associated with conductor I. A ground through the wheels of tlievvehicle and the track, coiildl be substituted for collector 39 and bus 40,V of course.

The rectifier discs shown associated with each 'pair of relays, are so poled, that alternating current willcperate both relays, while direct current of one polarity will operate only the upper relay of a pai-r, and direct current of the opposite polarity will roperate only the lower relay Thus, in the arrangement illustrated for station 324, with alternating current connected to collector shoe I4 by the marking pla-te I3, relay I1 will be energized on the positive half cycles in series with the lower rectier discs whichnow vshunt the lower relay, and relay 20 will operate on the negative half cycles in series with the upper .rectier discs which now shunt the upper relay. Both relays therefore ope crate. 'In a `similar manner, the positive half cycles of current connected to collector shoe I2 by the mark-ing plate `II will operate relay 23 but 'not relay 26, while lthe negative half cycles of current yconnected'to collector shoe I0 `through the marking `plate 9, will operate relay 32 but not relay 29.

The contacts, such as I3, I9 etc. of these com bination relays, are Varranged in a plurality 'of circuits corresponding to the 'various combinations. One lside of these circuits, all of which are open when the control or selector switches 35,36, 31 and 38 `are unoperated, is connected to the operating or switching collector shoe I5, which controls the trackside relay 5, while the other side is connected to the ground return collector Ishoe 39.

The selector switches 35, 36, 31 and 38, which are mounted on the outsideof the vehicle in an 'accessible position forquick and easy operae tion, are 'gang-type, hand-rotatable contact switches having two or three ccntact arms `which niov'e as "a unit, and Veach having also a pointer and a numbered dial, to facilitate setting the switches. Switch 35 is the dispatcher selector switch'which may be 'set in any one of four oinormal positions to select one of the dispatchers A, B, C yor D of Figure '2. This switch maybe preset bythe dispatchers themselves or, under some conditions of operatiom'm'ay vbe set by a supervisor located near the dispatching stations whowill distributethe returning vehicles among the available dispatchers as required. Switches 36, 31 "and 38 are the station j selector switches by means 'of which any handling station can be selected .according to its assigned three-digit number. The nundjredsjswitch 3e may be set to anyone er eight lcfr-normal positions, the nrst four f which will select a handling stationin the lower division X of Figure 2, and the last for of which will automatically select a station in the upper division Y. Switches 31 and 3B may be set to any one of four off-normal positions, to select the tens-and units digits, which are common to both divisions.

Figure 2 is a one-line diagram of a track layout The vehicle, on receiving power, starts out, and on passingoi the `siding A, goes on past the sidings B,VCv and 'D to track 43, past the division switch 443, and on into division X untilit reaches vbranch track 324, where the collector shoes I l2., I4. and .IB .will make 09ntact simultaneously, or approximately so, with the trackside .contact plates .9, II, I.3 and I5. `Since station 324 has its marking `plates connected as shown in Figure 1,Y negative halflcycle current will now flow from the ground bus 40 through collector .shoe 39, the hundreds relay 32, the upper rectiiier discs shunting relay 29, collector shoe I3, marking plate 9, `and the rectifier discs of strap 2 -to conductor I. VAt the same time positive half cyclesof current will `flow ...iro-m conductor .through the .rectiier discs of strap 3, marking plate II, collector shoe I2, tens relay 23, .the lower recti'er discs shunting relay 2,6, Land collector shoe 39 to the ground -bus 40. Alternate cycles of alternating current also ow' .through the units relays 20 and I1 by way of strap4., marking plate I3, andxcollector shoes I4 and 39. l

The combination relays 32, 23, 20 and I1 thereupon operate and complete an alternating current circuit .for the operation of the trackside relay .5.'1 This circuit is Las vfollows: bus 4D, collector shoe 39.,.makecontacts 33, point three in the center section A.of selector switch 36, the right hand contact arms lof switch 36, point three infthe right hand section of this switch, break contacts3, break :contacts 21, point two" in the left halfof selector switch 31, the two contact armsiof .this switch in series, point two" in the ,right .half of this switch,.zmake contacts 24, make :contacts 2|, point .four in the left half o f selector switch 38, the two contact arms 'of this 'switch .in series, A.point four in the right half of this switch, make contacts l-`I8, ycollector shoe I6, .track plate I5, .and the winding of relay 5 to'conductor I.

Relay f5 thereupon operates and locks, and 'closes contacts 1 to operate the electrically driven track switch 324, and the vehicle turns into the ,associated branch track. After the vehicle has cleared :the track switch, break fcontacts 8, located in ithejbranch track, will be opened momentarily 'by the vehicle in its passage. Relay '5 'will thereupon unlock and close break ycontacts 1 to reset the track switch for the main line. It should Vbe understood of course that .these track switches Vare provided with self reversing vcontacts or limit switches, which reverse at the extremity of -a movement in either direction to stop the 'movement in'that direction and prepare the movement in the opposite direction.

Upon arrival at handling station 324 .in the branch track, the vehicle may be stopped automatically vby a de-energized section in the power bus or trolley wire, or it may be stopped by an attendantpressing la button'on the vehicle to disconnect the motor. The exact `manner of starting and stopping is immaterial however, as far -as theoperation lis concerned.

VUpon being released from 'the lbranch track,

will .thereupon .complete a circuit for the operation fof. the trackside relay 5 at this .point as follows: -bus 4I), collector shoe 39, make contacts 34, y3| yand 28break contacts 25 and 22.. point one in the left half of selector switch 35, both contact arms in series, .point one in the right half of .switch 35, break contacts y. I9, collector shoe I6, a switching contact Lplate like I5, andy-the trackside relay to conductor I. The trackside Arelay and track `switcl'i 4.3-.I there upon operate and the vehicle passes into the siding, resetting the track switch .automatically after clearing the points, just as described for handling station 324.

In a large system vof this type, it is more than likely that the distribution of the retuning vehicles tothe dispatchers :will be controlled from a supervisors station S, located ynear the diS- patchers stations. In ,such a case, .the rdispatchers will .not `concern themselves with the dispatcher selector switch 35, but .only with 'the switches 3.5, 31, .and `38. If dispatcher .A therefore, .wishes `to dispatch a vehicle vto handling station .632 .in division Y, he vhas .only .toset selector switch 36 on point .siX, .switch 31 on point three and switch .3'8 on point "two, and then start the vehicle. The Vehicle kwill thereupon. pass out of the siding I,A as before and proceed along 'track 43 until it reaches division switch 443. By referring again 'to Tables I and II 'it will be seen that a 4-4-3 'mark-.ing on the -track plates at this Point will cause Athe operation of combination relays-32, 29, 26, '.23 and 2U. 'These relays will thereupon .complete a circuit. through the lleft arm of the :hundreds switch 36 for the operation .of the trackside relay 5 at this point as follows: bus .40., .shoe 39 make contacts 34,131, 28and 25,'point '"sX" in the left section of selector :switch 36 the left contact .arm of this switch, shoe I6, the trackside operating contact plate, Yand the trackside relay to conductor I. The trackside relay and track switch 443 then operateyand the vehicle passes into division Y and proceeds to the v'right along track 44, until it reaches the track switch 632.

Tables I and II indicate that track plates with a marking -6--3-#2 .will cause the operation of combination relays.29, 26 and I1 onthe Vehicle. These relays `therefore operata v.as lthe .vehicle reaches track switch 632, an-d close ya circuit ier the trackside relay 5.at this point through the right side'of the hundreds switch .36 .and through the tens and unitsvswitches `31.'and,38 as follows: ground bus 4I), slice I3,9, break .contacts 33, lpoint six inthe center section of selector .switch 36, the center and right hand contact arms ofthis switch in series, point six inthe right `hand section of 'this switch, make contacts y`3Il andl21, poi-nt "three-in theV left half of switch'31, both contact Aarms in series, point three l'in the :right half Jof this switch, bre-ak contacts 2'4 and `llI. point ltwdin the left :half of switch 38, point two in the vright half of .thissWitch'make .contacts I8and collector -sh-oe .I-S to ,contact plate I5 -and the .associated trackside relay `5. .The trackside .relay and track switch 632 vthereupon operate and the vehicle .passes .into branch track v63'2.

Upon being released from .branch track 63.2,. the vehicleproceeds left on track 441 vuntil itarrives `at the supervisors station S where it may stop or bestopped yif necessary, until the supervisor sets ythe dispatcher switch 35 and releases it, :whereupon it 'will-proceed, and-switch Litself into the selected-dispatcherfs siding.

9 In- Figure 3, the trackway equipment included bythe bracket 84 is like that` shown in Figure 1, except that this, being a smaller system, requires only tens and units marking plates, such as 51 and 59, the hundreds marking plate being omitted. The vehicle-borne equipment is also similar to that in Figure 1, except that only two pairs of combination relays are provided, and only three selector switches. The 1function of these selector switches is also slightly different. Selector switch 19. on the left for eX- -ample, selects the handling track, selector switch 80 in thel center selects a particular handling station on the selected branch track, and selector switch 8| on the right selects the Adispatcher station.

Figure 4 shows a one-line diagram of a typical track layout for use with the circuits of Figure 3. On the right are four dispatchers stations A, B,C and D located on branch tracks rather th-an sidingsas in Figure 2, and on the left are a number of handling station branch jtracks G, H, J, K, L, M, N, O and P, with four handling stations in each branch track. -A track switch is provided at the entrance of each branch track except the last, and the vehicles move always in a clockwise direction around the system as indicated by the small arrows. No division switches are required, since there is only one division. v

The number key for the stationary trackside connections to the combination marking plates, which yare now required at the handling station locations as well as the trackswitch locations, is as given in the Table III following. The-complete numbering scheme assumed for Figure 4 .is given in Table IV following. f

`TABLE In v Switch and `Srcz'o'n, strapping Units Digit Tens strapping Digit Through strap Trk, Strapping Relays Operated Tens Units Relays Operated Relays Disp. Station Swth Operated In tracing the operation oi this system, let it be assumed rst that dispatcher A wishes to dispatch a load to handling station H4, and have the empty vehicle return to his own station. To do this, the dispatcher will set selector switch 19 to lits second position to select the track switch H, in accordance with Table IV, and will set selectorswitch 86 in its fourth position to select the fourth station, in this `case station H4. The dispatcher will also at the same time set selector switch 8l to its -rst position, to select the track switch A, and will then apply powerto the vehicle. i

Thevehicle thereupon passes out of the branch track A, down on track 90, and left'on track 9i, until it' reaches the track switch H where the collector shoes 58, 60 and 62 will make contact with the trackside contact plates 51, 56 and'tl.

Since the combination marking plates 51 and 59 at this point are -connected for va 1 2 marking as shown in Figure 3 (see Tables III and IV), the combination relays and 1| will be operated by alternating current through strap 5l, contactplate 51, and collector shoes 58 and 82. 'Combination relay 61 will also operate, from the positive half cycles of current passing through strap 52, contact plate 59, and collector shoes` 66 and 82.

lRelays 15, 1l and 61 upon operating, close a circuit to the trackside relay 53 as follows: ground bus 83, collector shoe 82, make contacts 18,V left contact arm of selector switch 19, point two in the left section of this switch, make `contacts 14 and 10, point two of the center section of` selectorswitch 19, the center and right contact arms of this lswitch inseries, point two of the right hand section of the switch, break contacts 66, collector shoe 62,k track plate 6l, and trackside relay 53 to conductor 50.

" Relay 53 thereupon operates and locks through f its make contacts 54 to ground at break contacts 56, and at the same time closes make contacts55 to operate the track switch H, thereby causing the vehicle to turnin on thek branch trackv H. When vthe vehicle has vcleared the track switch, it opens the trackway break contacts 56, thereby unlocking relay 53, which thereupon releases and resets track switch H for main line operation.

The vehicle now proceeds along branch track H until itfreaches handling station H4. Since the fourth station in each handling track has its combination marking plates connected as shown in the'second part 'of TableiIV, which indicates a 3-4 marking per Table III, combination relay 1i alone will operate at this'y point. Relay 1| will upon operating', complete a circuit for the trackside relay 53' at station H4, as follows: ground bus 83, collector shoe 82, break contacts 11, left contact Varm of selector switch 86, point four of the left hand `section of this switch, make contacts 13,'break contacts 59, point four of the -center section of selector switch 80, center and right hand contact arms of this switch in series, point four of the right hand section of the switch, break contacts 65, collector shoe 62, track contact plate 61, and relay 53 to conductor 5l?.

Relay 53 at station H4 now operates and locks,

and at contacts corresponding to make contacts 55 closes a circuit to a"power off` relay, shown in dotted lines, which disconnects power from ythe track section facing the station H4, causing the vehicle to stop. Break contacts 56 in this case, representa manually operated switch under the control of an attendant or workman at the handling station. To start the vehicle again,- it is aclaro@ onlyy necessary te Operate switch 5B. momentarily, to unlock relay 53 and release the power-off relay.

The vehicle now advances again under its WD power, and on passing out ofbranch track H proceeds to the right on track S2 until it reaches track switch A. By reference to the third section of Table IV, it is seen that the track Contact plates at this point Vhave a 4-1 marking per Table III, which will cause combination relays 61 and 63 to operate. When relays B'I and 63- operate, thci7 immediately close a circuit to the track-side rela-il7 -53 at this point as follows: ground bus 83, shoe 82, break contacts: 16, point onein the left hand section of selectorgswitch 8|, left contact. arm of this switch, break contacts 12, make contacts 68, point one in the center section of switch 8l. center and right contact arms in series, point one in the right. section of this. switch, make contacts 64, collector shoe 62, track plate BI, and relay 53 to conductor 50. Trackside relay 53 upon operating, locks in the usual Wayand operates trackswitch A, to pass the vehicle back into the dispatcher branch track A, the vehicle resetting the switch as it advances, as previously explained. Upon arriving at the dispatchers station, it may stop automatically due to a normally dead section of bus at this point or it may be stopped bythe dispatcher operating a switch or a key or a push button, as preferred.

To dispatch a vehicle to handlingv track P, which must beV the last branch track, the dispatcher will not set the handling track selecting switch 19, to any handling track but will set it `rather on the normal or zero point. The vehicle will, therefore pass by all of the handling track switches without operating any of them, and will perforce, pass i-n onto track P since there is Ano track switch at this point, and will stop at any selected station on this track, according to the seting of selector switch 80'. Similarly, to route a vehicle back to dispatching track D, it isonly necessary to set selector switchl on the Zero point, and the vehicle will pass by the track switches A, B and C on its return journey, and enter track D.

The trackside contacts and the carriage contacting shoes in the upper part of Figures 1 and 3 have been shown in a straight line in the direction of the trackway'for convenience only. In the application of the invention, Vit will be obvious that such an arrangement might cause -false operations, should the combination shoes such as I4, I2 and I0 be allowed to brush over track `contact I5. It is therefore contemplated that the trackside contacts 4would normally be placed side by side, or staggered, so as to avoid unnecessary operations of the combination relays, as well as the aforementioned possible false operation of the trackside relay,v For similar reasons, the operate trackside contacts VI5 and 6I should be made shorter than the other contacts, and. so set in relation to them that contact is made with sa-id contacts I5 and 6I by the opera-te shoe on the carriage, only after the combination relays on .the carriage have operated, and is broken before .the combination relays start to release.

What is claimed is:

1. YIn an `electric `conveyor system, a track, a self propelled vehicle moving along said track, a -rst group of branch tracks, a plurality of receiving stations in each branch track .of said first group, a second group of branch tracks, a dispatching station in each branch ytrack of said second group, a carriage stopping means at each 1'2 receiving statica and. a track switching means at the entrance t0 each branch track. a switching point at each branch track entrance and a stopping point at each receiving station, a plurality of sets of relays on said vehicle, contacting shoes carried on said vehicle and each shoe connected to a corresponding relay set, contacts on said vehicle relays, track contacts corresponding respectively to said shoes at each switching and stopping point marked electrically in diierent ways to cause the operation'of said relay sets in dilerent combinations as said contacting shoes simultaneously engage the corresponding track contacts, a dilferent combination of said vehicle relays being operated at each switching and stopping point responsive to such engagement, combination circuits also corresponding to said switching and stopping peints being partially completed through the contacts of said vehicle relay sets in response to the operation of each relay combination, said combination'circuitsl comprising a rst group of, combination circuits corresponding respectively to said receiving station switching points, a second grou-pcf combination circuits corresponding ree.

spectively 'tosaid receiving station stopping points, -and a third group of combination circuits corresponding respectively to said dispatching station switching points; va iirst manually operated preselectingmeans on said carriage for cempleting one of said partially completed combination circuits in said first group of circuits to eiect the operation of the track switching means at the entrance to a preselected one of 'said receiving station branch tracks, a second manually Operated preselecting means on said carriage for completing one of said partially completed combination circuits in said second group ofy circuits to effect the operation of thefvehicle stopping means at a preselected ene of said receiving stations, and a third manually operated preselecting means on said carriage for completing one of said partially completed combination circuits in said third group of circuits lto effect the operation of the track switching means at the entrance to a preselected one of said dispatching station branch tracks.

2. In a conveyor system, a track, a carriage propelled along said track, a plurality of receiving station branch tracks, a first and a second division including different ones of said receiving station branch tracks, a plurality of dispatching station branch tracks, a trackswitch at the division entrance point and at the entrance to each branch track, a plurality of relay sets on said carriage, a track contact at each trackswitch location for each said relay set on said carriage, means for causing the operation of said relay sets in different combinations from said' trackside contacts upon the arrival of said carriage at the correspending trackswitch location, a different combi? nation of said relays being operated at each said trackswitch location, a rst group of contacts on said ivehiclegbcrne relay sets, a rst group of circuits connected to said first group of relay contacts and corresponding respectively to said receiving station branch trackswitches, a second group gf contacts on said vehicle-borne relay sets, a second group of circuits connected to said secfond group of -relay contacts and corresponding respectively to said dispatching station branch track switches, an additional circuit connected to said second group of contacts and corresponding to said division entrance trackswitch, a plu.- rality 01 hand operated preselectingvdevices on said carriage for determining which'of said .i'lrst group of circuits will be preselected to control the i513 entrance trackswitch a a preselectedfone :of said receiving branch tracks, means on one of said same preselecting deviceswhen in certainof'its i r`circuits will be preselected to controlthe entrance trackswitch at a preselected one offsaiddispatching station branch tracks,` and means for completing said preselected circuits and thereby operating therespective associated ltrackswitches automatically whenever said carriage reaches said' respective preselected trackswitches.

v3. In a conveyor.system,va track, a carriage propelled along said track, a plurality of Icontacting shoes'on said' carriage; a 'pluralityof relay sets on said carriage, leach set connected toa different one of said contacting shoes, a plurality of switching 'points along said track, 'a plurality of trackside contact members at each of said switching point, thev same number of contact members being used at each switching point, each of the said trackside contact members ateach switching point being markedfwithany one 'of a plurality of diieren't electrical potentialsfdiiierent combinations of the said potentials being employed at each switching point, a single-digit number assigned to each one of said plurality of electrical potentials so `that each potential combina-l tion maybe represented'by a plural digit numberv v, having a digit for each of said respectivev trackside contact members atfeach switching pointv to identify said switching points, meansincluding said contacting shoes eiective as-sa'id carriage arrives at' each switching point for causing said relay sets to operate simultaneously from 'said' trackside contact Amembers, in diierent combinations corresponding to said switching pointsfand said corresponding plural digit'numbersfcont'acts on-said relay sets, a group of circuits through the contacts of each of said relay sets for controlling pare predetermined ones ofv lsaid circuits, and

means to complete saidcircuits through said contactsA and said presettable meansf'andto operate preselected 'one-s of said entrance lswitches thereover for directing said vehicle intotheassolciated branch track, whenever the operated yre#- lay-combination coincides with the setting of'fsaid hand operatedrneans. f l 5. In a conveyor system,r a trackya` carriage propelled along said track, switching points along said track, receiving stations associated with #some of said switching points and dispatching 'stations associated with others of saidswitching points, trackside contacts at each switchinglpoint and'contacting shoes on saidcarri'age for engaging them momentarily in passing, the trackside 'contacts atr veach yswitching@point'v being identical in both ynumber andrelative position with'fth'ose lo'i everyY other switching point and 'withI said shoes, potential sources of diierent polarity characteristics, trackside cross-connecting means for separately connecting vthe individual track'- side contacts at each switching pointto any one of said potential-sources, thereby to set up a characteristic combination of potentials at each switching point, a plurality of. relay groups on said4 carriage, each or said relay groups being switching operations at said switching points and reach circuit corresponding respectively to the vdifferent digits of said identifying switching'point numbers, a hand operated preselecti'ng device on said carriage for each' said relay set, said preselecting devices beingr set in advance in accordance with said identifying switching point numbers to preselectcertain of said circuits in each said circuit group and connect them together to prepare a switching operation at a preselected oneof said switching' pointsy and means including 'a switching control contactingjshoe on said-carriage for completing a circuit through said prepared circuits atsaid preselected switching point upon the arrival of said carriage at said preselected switching point and the operation of said relay sets, thereby to complete a switching operation atsaid preselected switching pointt connectedvto one of said contacting `shoes and ythe relays within each groupV having vuni-directional circuit elements associated therewith to cause the relays within a groupto operate "selectively depending `on the polarity characteristic of the potential encountered by the contacting shoe upon its engagement with a corresponding trackside contact;fcontacts on said relays, anrst group of circuits connected to said relay contacts and corresponding respectively to said receiving station switching points, a second grou'pof circuits connected to said'relaycontacts and'corresponding respectivelyto said dispatching sta- 4. In a' conveyor system, Va track includingtion lswitching points, manually operatedp'reselecting devices on said carriage for preselecting one of said firstgroup of circuits to control a switching. operationvat a predetermined one of said receiving stations, a different-manually operated preselecting device on said" carria'ge for preselecting one of'said second group'offcircuits to control a switching operation at a predetermined one of said dispatching stations, a switching-shoe on4 said carriage, a tracksideswitching contact element at each switching -pointf'and means including said switching shoe and trackside Vswitching contact element for Vcompleting said preselectedk circuits through lsaid relay contacts and said preselecting devices in series "to effect Said switching operations whenever said carriage reaches said' respective l'preselected switching points and engages allol the saidconvtracks along saidv track, entrance switches for said branch ftracks, a setv Vof tracksidefcontact 15 sources ofl different polarity characteristics, trackside cross-connecting means' for separately connecting the individual tracksidef contact members of' each set to: any one of said potential sources, thereby toY mark each set with a given combination of' potentials, a corresponding set of contact shoesf on Isaid. vehicle, said contact shoes: being relatively positioned forl concurrent engagement' with the individual contact members of any set, a corresponding set of. relay groups on said vehicle, each of' said relay groups being connected to one of said. contact shoesl and the relays within each. group having uni-directional circuit elements associated therewithto cause the relays.' within a group to operate selectively depending on the polarity characteristic of the potental encountered by the contact shoe. upon its engagement with acorresponding contact member, whereby the relays on the vehicle are oper'- ated inA varying combinations each time thev vehiclef` approaches. anv entrance switch, contactsA on said relays, manually preset preselecting` means onsaid vehicle for interconnecting the contacts of the relays. on the vehicle` in a pattern characteristi'c of a desired entrance switch, andan entrance switch operating. circuit completed through said relay vcontacts and said manual. preselecting meansv whenever the setting of said cross-connecting means and the setting of said manual preselecting means correspond to each other.

7l In a material handling system, a track, a carriage moving along' said track, aplurality of switching points located at intervals along said track, avv set of trackside contact members at each switching point, potential sources of diierent polarity characteristics,l trackside cross-con ynecting means for separately connecting the individual trackside contact members of eachV set to any one of said potential sources, thereby to mark' eachset with a given combination of potentials, a corresponding set of contact shoes on said carriage, sa-idx contact shoes being relatively positioned for concurrent engagement with the individual contact members of any set, a corresponding. set of relay groups on said carriage, each of said relay groups being connected to one of said contact shoes and the relays within each groupv having uni-directional circuit elements associated-` therewith to cause the relays within a group to operate selectively depending on the polarity characteristic of the potential encoun- 1 tered by -the contact shoe upon its engagement with a corresponding contact member,l whereby the relays onv the carriage are' operated inl varying combinations each*y time the carriage approaches a switching point', contacts on said; relays, manually' pre-set preselecting means on said carriage for interconnecting' the contacts of the relays on the carriage in a pattern characteristic of a desiredl switching point, a switching .shoe on. said carriage, a trackside switching contact at each switching point, and a circuit closed Vthrough saidmanual preselecting means andy the contacts of said. combinationally operated. relays in series responsive to the engagement of said l switching shoe and said switching contact at' a preselected switching. point for causing a track switch operation at said. preselected switching point, the range of engagement, length-wise of said track, between said switching shoe and said switching'l contact being shorter at the leading endthereoi than-the range of engagement between said contact shoes and contact members over which said: relays are operated, whereby said A#I6 switching circuit is closed subsequent to the closure of said relay operating circuits, and ltrack switching operations response to incompletcly setup relay combinations are avoided.

8. In a material handling system,"a track, a carriage moving along said track, a plurality of switching points located at intervals alongY said track, a set of trackside' contact membersY at each switching point, potential sources of different polarity characteristics, tracksidel cross-connecting means for separately connecting the individual trackside` contact members of each set tov any one of said potential sources, thereby to mark each set: with a given combination of potentials, a corresponding set of contact shoes on said carriage, said contact shoes being relatively positionedv for concurrent engagement-with the individual contact members of any set, va corresponding set of relay groups on said carriage, each of said relay groups being connected to one of said Contact shoes and the. relaysY within each groupA having. uni-directional circuit elements associated therewith. to cause` the relays within a group to operate selectively depending on theV polarity characteristic of the potential. encountered bythe contact shoe upon itsl engagement with a corresponding contact member, wherebyl the relays on the carriage' are operated in varying combinations each time the carriage approaches a switching point, contacts on said relays, manually preset preselecting-'means on said carriage for interconnecting the contacts of the relays on the carriage in a pattern characteristi'c oil 'a desired switching point, a switching shoe on said. carriage, al trackside switching contact at each switching point, and a circuit closed through saidv manual preselectingmeans andthe contacts of said combinationally operated relays in series responsive to the engagement of said switching shoe and said. switchingt contact at a preselected switching point for causing aV track switch operationv at said preselected switching point; the range of engagement, lengthwise' `of said` track, between said switching shoe vand switching contact-being shorter at both the leading. and trailing end thereof than the range of engagement between said contact shoes and contact members overV which said relays are operated, whereby said switching circuit is closed subsequent to the closure of said relay operating circuits and is opened prior to the opening of said relay operating circuits, and track switching operations in responsev to* incoifnpletelysetup or partially released' relay combinations are avoided. f l f KURT MULLERHEM,

'l REFERENCES ,CITED 'Ihev following references are of record inthe file of this patent: f

UNITED STATES PATENTS Number Name Date 1,208,060 Weller et al. Dec. 12, 1916 1,243,457 stuart oct y1e 191.7 1,381,317 Loughridge June 14, 1921 2,176,458 Goddard oct. 17, 1939 2,194,057 simpson Mar. 19, 1940 2,299,840 Purcell oet. 13, 1942 2,320,150 Loughridge May 25. 1943 2,486,222V spafford oct-'251 1949 FOREIGN PATENTS Nunlgeg 3 Country Date 3 Great Britain df 190g YMar 3, 1910 3.1411112- Great Britain June 24,1929 

